Lamp sealing apparatus



Oct. 25, 1955 2 H. E. BAKER ETAL 2,721 ,422

LAMP SEALING APPARATUS Filed Jan. 30, 1953 6 Sheets-Sheet 1 Oct. 25, 1955 H. E. BAKER ET AL LAMP SEALING APPARATUS 6 Sheets-Sheet 2 Filed Jan. 30, 1953 Oct 1955 H. E. BAKER ET AL LAMP SEALING APPARATUS 6 Sheets-Sheet 5 Filed Jan. 30, 1955 Oct. 25, 1955 H. E. BAKER ET AL 2,721,422

LAMP SEALING APPARATUS Filed Jan. 30, 1953 6 Sheets-Sheet 4 lllllll Oct. 25, 1955 H. E. BAKER ET AL 2,721,422

LAMP SEALING APPARATUS Filed Jan. 30, 1953 6 Sheets-Sheet 5 Oct. 25, 1955 H. E. BAKER ET AL 2,721,422

LAMP SEALING APPARATUS Filed Jan. 30, 1953 6 Sheets-Sheet 6 INVENTORS HAROLD E. BAKER JOSEPH H. BROOKS ,TTOlNE United States Patent LAMP SEALING APPARATUS Harold E. Baker, Danvers, and Joseph H. Brooks, West Peabody, Mass., assignors to Sylvania Electric Products Inc., Salem, Mass., a corporation of Massachusetts Application January 30, 1953, Serial No. 334,302

12 Claims. (c1. 49 2 This invention relates to the manufacture of elongated tubular electrical devices and more particularly to the manufacture of fluorescent lamps.

In the manufacture of fluorescent lamps, it has been the practice generally heretofore to seal a lamp mount to each end of the lamp tube on a rotatable turret type machine such as that shown in U. S. Patent 2,349,822 issued May 30, 1944 to Roland M. Gardner. In this type of apparatus, a plurality of heads are disposed about the periphery of a turn-table which is indexed to bring the heads thereon to a plurality of work stations. The lamp tube is maintained in a vertical position in the head while a lamp mount is sealed to one end thereof. Then the lamp tube is inverted, either manually or by a tube inverting apparatus such as that shown in U. S. Patent 2,597,283 issued May 20, 1952 to Joseph H. Brooks, and a lamp mount is sealed to the other end thereof.

Although this type of apparatus for sealing lamp mounts to a lamp tube to provide a sealed lamp envelope has proven very satisfactory in many respects, it is characterized by certain features which limit the speed with which the sealing operation may be effected. For example, the speed with which the sealing operation may be effected is limited by the speed with which the machine may be indexed, the dwell time necessary for effectuation of the sealing operation, and the speed with which a lamp tube may be inverted.

Accordingly therefore, an object of this invention is to seal lamp mounts to the ends of a lamp tube simultaneously instead of sequentially.

Another object is to provide an apparatus for sealing lamp mounts to lamp tubes at speeds substantially higher than those speeds attainable with the type of apparatus described above.

A further object is to seal a lamp mount to an end of a lamp tube while the lamp tube is disposed horizontally instead of vertically.

Further objects, advantages and features will be apparent to those skilled in the art from the description below of the specific embodiment of our invention illustrated in the accompanying drawings.

In the embodiment of our invention described below and illustrated in the accompanying drawings, lamp mounts are sealed to the ends of an elongated lamp tube simultaneously on a continuous motion conveyor with the lamp mounts and the lamp tube rotating about their own axes.

In the specific embodiment of the apparatus of our invention illustrated in the drawings:

Figure l is a plan view of the lamp sealing apparatus.

Figure 2 is an elevational view of the drive side thereof.

Figure 3a, 3b is a sectional view taken substantially along the line 3a, 3b-3a, 3b of Figure 1.

Figure 4 is a sectional view on an enlarged scale taken along the line 44 of Figure 3a showing the means employed to lock the bolt of the mount supporting mechanism in its advanced and retracted positions.

2,721,422 Patented Oct. 25, 1955 Figure 5 is a sectional view taken along the line 55 of Figure 3b showing the mechanism for rotating and arresting the rotation of the tube-supporting cradle which is shown in the open position.

Figure 6 is a fragmentary detail, partly in section, of a portion of the tube-supporting cradle, looking in the direction of the lines 6-6 of Figure 5.

Figure 7 is a fragmentary plan view of the tube-supporting cradle showing the means employed to lock a lamp tube therein.

Figure 8 is a sectional view taken along the line 8-8 of Figure 7 showing the means employed to lock a lamp tube in its cradle, this means being shown in the closed position, as shown in dotted lines in Figure 7.

Figure -9 is an enlarged fragmentary plan view sequentially illustrating the feeding of a lamp mount from a conveyor to a spindle which supports the mount during the sealing operation.

Figure 10 is an enlarged sectional view taken along the line 1010 of Figure 9 showing the mount-carrying clips and the drive wheel of the mount conveyor.

Figure 11 is an enlarged sectional view of the burner assembly.

Figure 12 is a sectional view taken along the line 1212 of Figure 11 showing the burner port.

Referring now to the drawings, particularly Figures 1, 2 and 3a, 3b, the specific embodiment of the lamp sealing apparatus shown therein is mounted on an angleiron frame 20. Broadly speaking, this apparatus comprises a pair of endless conveyor chains 22 which carry a plurality of heads 24 mounted thereon through a path along which two banks of heating units 26 for sealing lamp mounts to the ends of lamp tubes are disposed. Lamp tubes may be inserted into the heads 24 manually or they may be fed thereto automatically by a suitable feeding apparatus not shown. Lamp mounts are automatically fed to the heads 24 by a pair of mount feeding mechanisms 28, these mechanisms being disposed opposite one another at the loading end of the lamp sealing apparatus.

The endless conveyor chains 22, which carry the heads 24, are mounted on sprocket wheels 30 at the loading end of the lamp sealing apparatus and sprocket wheels 32 at the unloading end thereof. The conveyor chains 22 are supported by and ride on tracks 23 which are mounted on the frame 20. The sprocket wheels 30 are mounted on an idler shaft 34 which is supported by the frame 20. The sprocket wheels 32 are mounted on a drive shaft 36 which is supported by the frame 20. Drive shaft 36 is driven by a motor 38 which is connected thereto through a gear reduction mechanism 40 associated with motor 38, chain 42, sprocket wheel 44 mounted on shaft 46, and gear reduction mechanism 48 through which the rotary motion of shaft 46 is transmitted to drive shaft 36.

Since the pair of mount feeding mechanisms 28 disposed at opposite ends of the loading end of the lamp sealing apparatus, are driven by separate, similar means, only one of the driving means will be described. Each of the mount feeding mechanisms 28 is driven by a gear 49 mounted on the shaft 34 at each end thereof. A shaft 50, which is supported by the frame 20, has a gear 52 mounted thereon which meshes with the gear 49. A sprocket wheel 54, mounted on shaft at each end thereof, is connected by means of an endless chain 56 to a sprocket wheel 58 mounted on a shaft 60 supported on the frame 20. The shaft 60 drives the mount feeding mechanism 28.

Since the pair of mount feeding mechanisms 28 are identical in construction, only one of them will be described. The mount feeding mechanism 28, which is supported on an angle-iron framework 62 mounted on the lamp sealing machine frame 20, comprises an endless metal belt 64 to which a plurality of mount-carrying clips 66 are attached. The belt 64 is driven by a wheel 63 mounted on the shaft 60. The wheel 68 is channeled about its periphery to define a guiding channel '71) for the belt 64 and it is also notched to define a plurality of recesses 72 which are engaged by bosses 74 on the belt 64, thereby insuring a positive driving of the belt (Fig. The belt 64, which moves in the direction indicated by the arrow in Figure 2, passes around wheel 68, thence around wheel '76 which turns on the upper end of shaft 78 which is supported by the framework 62, thence around wheel 80, thence around wheel 82 which turns on the lower end of shaft '78, and thence around wheel 63 as mentioned above. Each of the wheels 76, 80 and 82 is channeled about its periphery to define a guiding channel 70 for the belt 64, just as wheel 68 is so formed as mentioned above. Wheels 81), 76 and 32 are channeled deeply enough to accommodate the bosses 74 on the belt 64. Since the wheeis 68 and 815 are disposed in a vertical plane and wheels 76 and 82 are disposed in a horizontal plane, the belt 64 is twisted accordingly, as shown in the drawings, to provide for its proper travel over these wheels.

Since the two banks of heating units 26 which effect the sealing of lamp mounts to the ends of a lamp tube are identical in construction, only one of them will be described. Each bank of heating units 26 comprises a plurality of burners 84 each of which is pivotally mounted at 86 on a burner supporting rod 83 which is in turn supported from the frame 20. Each burner 84 is connected by means of a flexible tube 91 to a rigid tube 92 mounted on and bridging illuminating gas manifold 94 and oxygen manifold 96, these manifolds being mounted on the frame 20. Gas and oxygen are fed from a supply (not shown) to the manifolds 94 and 96 respectively and thence through the tubes 92 and 96 to the burner 84. Each burner 84 is provided with suitable controls (not shown) by means of which adjustment of the gas and oxygen flow may be made.

During the period of time when the endless conveyor chains 22 are carrying the plurality of lamp-holding heads 24 from the loading end of the lamp sealing apparatus to the unloading end thereof, the burners 84 of the two banks of heating units 26 are moved into and out of heating relationship with the ends of the lamp tube a plurality of times. This is accomplished by the provision of means for reciprocating the burner-supporting rods 88 of the heating units 26 along their longitudinal axis and means for oscillatingthe burner-supporting rods 88 about their longitudinal axis at each end of the reciprocating stroke thereof. At the beginning of the reciprocating stroke of the burner-supporting rods 88, the rods 88 are oscillated to move the burners 84 into heating relationship with the ends of the lamp tubes. The burners are maintained in this position until the rods 88 reach the end of their stroke, at which time the rods are oscillated to raise the burners 84 out of heating relationship with the ends of the lamp tube and move them out of the path of the lamp-holding heads 24. The return reciprocating stroke of the rods 88 is then effected, with the burners 84 maintained in their elevated position.

The means for reciprocating the burner-supporting rods 88 along their longitudinal axis will now be described, reference being made initially to the left hand side of Figure 2. The drive for reciprocation of the burner supporting rods 88 is taken off of shaft 46 by means of a gear 98 mounted thereon. The gear 98 meshes with gear 106 mounted on shaft 102. The end of shaft 102 adjacent to gear 100 has a miter gear 104 mounted thereon. The miter gear 104 transmits rotary motion of shaft 102 into rotary motion of shaft 106 through miter gear 168 which meshes with gear 104 and which is mounted on shaft 106. The shaft 106 extends across the full width of the lamp sealing apparatus frame 20 and is supported thereby. The shaft 106 has a cam 110 mounted thereon adjacent to each end thereof, the cam 110 having a cam track 111 formed therein. From this point on, a pair of separate, identical mechanisms are employed for reciprocating the pair of burner sup porting rods 88 and therefore only one of them will be described. Rocker arm 114, pivotally mounted at one end thereof on the frame 20 at 116, has a cam follower 112 mounted thereon intermediate the ends thereof which rides in cam track 111 of earn 110. A connecting rod 118 connects the free endof the rocker arm 114 to a lever 120 mounted on one end of a shaft 122. The shaft 122 is supported in a pair of bearing brackets 124. The other end of shaft 122 has a lever 126 depending therefrom. The free end of lever 126 is connected to extension 128 of burner supporting rod 88 by means of a connecting rod 130 which is provided with ball and socket joints at each end thereof to permit it to absorb the oscillation of burner supporting rod 88 and prevent the transfer of this motion back into the burner supporting rods reciprocating mechanism. The extension 128 of burner supporting rod 88 is supported by a bearing bracket 132 mounted on and depending from the frame 20.

The means for oscillating the burner-supporting rods 88 about their longitudinal axis will now be described. There are four of these mechanisms, two on each side of the machine, as shown in Figures 1, 2, 3a and 3b. Since they are identical in construction, only one will be described. Referring first to Figure 2, the shaft 162 has a cam 142 mounted thereon which is engaged by a cam follower 144 disposed on one end of a rocker arm 146 pivotally supported at 143 on the frame 20. A connecting rod 150 connects the other end of rocker arm 146 to the rod 152 upstanding on burner-supporting rod 88 through ball and socket joints 154.

Since the heads 24 which are mounted on the endless conveyor chains 22 are identical in construction, only one of them will be described, reference being had particularly to Figs. 3a and 3b. The several mechanisms which comprise the head 24 are mounted on a bedplate 156 which is attached to the conveyor chains 22. A mount supporting mechanism, designated generally by the numeral 160, is disposed at each end of the bedplate 156 and a tube-supporting cradle or holder, designated generally by the numeral 162, is disposed at the center of the bedplate. Ball-bearing wheels 163, at each end of the bedplate 156, ride on tracks 167 (Fig. 2) during the return of the heads 24 from the unloading end to the loading end of the apparatus, thereby supporting the heads during this portion of their travel.

Referring now to Figures 3a and 7, the tube-supporting cradle 162 comprises a pair of spaced horse-shoe-shaped bearings 164 connected to one another by three tie rods 166, the bearings 164 being rotatable in fixed plates 168 upstanding on the bedplate 156. The lamp tube 11 is seated on a pair of buttons (Fig. 5) on the inside face of each of the bearings 164 and is securely retained therein by a locking device designated generally by the numeral 1'76 (Figs. 3a, 7 and 8). The tube locking device 176, which is shown in detail in Figure 8, comprises a block 172 mounted on the tie rods 166, a shaft 174 supported in the block 172, a tube-locking finger 17 6 mounted on one end of the shaft 174 and a miter gear 178 mounted on the shaft 174 adjacent to the other end thereof. The tube-locking finger 176 is tapered at one end to define a camming face 130 for operation thereof and is provided at the other end thereof with a spring-loaded button 182 which, when the finger 176 is actuated, moves into and out of frictional engagement with a lamp tube 11 to alternatively hold it securely in the cradle 162 on the buttons 165 of the bearings 164 and free it for release therefrom. The miter gear 178, which is mounted on the shaft 174, meshes with miter gear 184 which is on oneend of shaft 186. Shaft 186extendsthrough one of the bearings 164 (Fig. 7) and has a segmental gear 188 mounted on the other end thereof. A segmental .gear 190, mounted on the bearing 164 at thisend of the cradle 162 is disposed between segmental gear 188 and bearing 164. Segmental gear 188 coacts with segmental gear 190 to completely encircle the lamp tube during the sealing operation and to form a complete gear thereby providing the means through which the cradle 162 maybe rotated. The segmental gear 190 has a projection 192 upstanding on a face thereof which constitutes a stop for the segmental gear 188 when the latter gear is closed with respect to the former gear. The segmental gear 188 has a plate 194 mounted thereon which has a projection 196 upstanding on a face thereof, the purpose of which will be described below. A pin 198 on plate 194 of segmental gear 188 and a pin 200 on segmental gear .190 support a spring 202. The spring 202, due to the relative location of its mounting pins 198 and 200 with respect to the shaft 186, loads the segmental gear '188 in both its open and its closed positions.

As was mentioned above, the cradle 162, which supports the lamp tube, is rotatable. Rotation of the cradle 162 within the fixed plates 168 is accomplished by rotation of the segmental gears 188 and 190 when they are closed with respect to one another. Segmental gears 188 and 190 mesh with gear 204 mounted on shaft 206 which is supported by the bedplate 156 on the underside thereof (Figs. 3b and 5). Sprocket wheel 208, which drives shaft 206, is mounted thereon and engages the middle chain 210 of a triple chain conveyor 212 (Figs. 1 and 3b). The triple chain conveyor 212 is mounted on sprocket wheels 214 on driven shaft 216 and sprocket wheels 218 on drive shaft 220, shafts 216 and 220, being supported by the frame 20. Conveyor drive shaft 220 is driven by a motor 22 (Fig. 2) through a suitable variable speed reduction gear (not shown), sprocket wheel 224 on shaft 226, and chain 228 which connects sprocket wheel 224 to sprocket wheel 230 on shaft 220.

Since the cradle 162 is rotated during the sealing operation, means must be provided for arresting this rotation at or near the loading and unloading ends of the apparatus to permit feeding of the lamp tube at the loading position and releasing of the sealed lamp at the unloading position. This means will now be described, ref erence being had particularly to Figures 3b and 5. A ratchet wheel 232, with only one tooth formed on the periphery thereof, is mounted on shaft 206 near the sprocket wheel 208. A pawl 234, engageable with ratchet wheel 232, is mounted on one end of a spring-loaded shaft 236 which is supported in blocks 238 mounted on the bedplate 156. One end of a lever 240 is mounted on the other end of the shaft 236, the other end of the lever having a cam follower 242 mounted thereon which rides on cam track 244 (Figs. 1, 3b and 5) which is mounted on the frame 20. The shaft 206 is provided with a friction clutch which, in cooperation with the pawl 234 and ratchet wheel 232, prevents transmission of the rotational motion of the shaft 206 and the sprocket Wheel 288 to the cradle 162 shortly before the sprocket wheel 208 leaves the chain 210. This is done to make sure that the rotating cradle 162 comes to rest in a position which will permit the release of the sealed lamp therefrom at the unloading end of the apparatus. The friction clutch comprises a fiber washer 247 disposed on shaft 206 between the hub of sprocket wheel 208 and a spring-loaded metal washer 249.

As was mentioned above, there is a mount supporting mechanism 160 located at each end of the bedplate 156. Since they are identical in construction, only one of them will be described. Referring now to Figure 3b, the mount supporting mechanism 160, which is supported by a pair of plates 246 upstanding on bedplate 156, comprises a bolt 248 slidably disposed in a sleeve 250 and having a mount spindle 252 mounted on an end thereof.

.6 The sleeve 250, which is rotatably supported in the plates 246, is rotated by shaft 206 through gear 254 on shaft 206 and gear 256 which is mounted on sleeve 250 and which meshes with gear 254 (Figs. 3a, 3b and 4). 7

Means are also provided for effecting reciprocating movement of the bolt 248 within its sleeve 250. The sleeve 25'0 is provided with an elongatedslot 258 (Figs. 1 and 4) through which a pin 260, upstanding on bolt 248 extends. A cam follower 262 mounted on pin 260 engages a cam track '264 (Fig. 1) at the loading end of the lamp sealing apparatus and a cam track 266 (Figs. 1, 3a and 3b) at the unloading end thereof. The contour and relative disposition of the cam rtracks 264 and 266 is such that the bolt 248 is advanced at the loading end and retracted at the unloading end. In order to define the limits of the reciprocating stroke of the bolt 248, insure the positive retention of the bolt thereat when so desired and to prevent accidental and .un-intentional dislocation of the bolt therefrom, the sleeve 250 is provided with a collar 268 with a pair of springs 270 disposed in holes 272 drilled therein at opposite sides thereof (Fig. 4). These springs 270 load balls 274 which are disposed in the wall of sleeve 250 and which are engageable with indentations 276 formed in bolt 248. There are two pairs of indentations 276 formed in the 'wall of bolt 248, one pair being disposed so that the spring loaded balls 274 will engage them when the bolt 248 is in its advanced position and the other pair thereof being disposed so that the springloaded balls 274 will engage them when the bolt 248 is in its retracted position.

Since it has been found desirable to provide means for varying the end thrust of the bolts 248 of the mount supporting mechanisms at various stages of the operating cycle, this means will now be described. A bell-crank lever 278 (Figs. 3a and 3b), pivotally mounted on each end of bedplate 156 at 280, has a cam follower 282 on one end thereof and a yoke 284 on the other end thereof. The inside faces of the upper ends of the yokes 284 are provided with bearings 286 (Fig. 1;) which are disposed in a groove 288 (Figs. 3a and 3b) in a collar 290 mounted on sleeve 250 and ride therein during rotation of the sleeve. Each of the bell-crank levers 278 is loaded by a spring 292 on a pin 294 which connects the lever 278 to the adjacent plate 246. The spring 292 urges the sleeve 250 forward, retraction of the sleeve 250 being effected when the cam follower 282 engages and rides along cam track 296 (Fig. l) and cam track 298 (Figs. 1, 3a and 3b). In view of its purpose, the stroke of the sleeve 250 is quite short, being limited on one end by the plate 246 against which vthe collar 290 abuts when the sleeve is advanced by the spring 292 and on the other end by the relative location of the cam tracks 296 and 298 when they are engaged by the cam follower 282.

Referring now to Figures 3a and 3b, the bedplate 156 is provided with a pair of puddling devices mounted thereon in a position to work on the heated ends of the lamp tube and aid in the formation of a satisfactory seal between the ends of the lamp tube and the lamp mounts. Each puddling device comprises a springloaded lever 300 pivotally mounted intermediate its ends on a rod 302 supported on the bedplate 156. The lever 300 has a puddling wheel 304 rotatably mounted on one end thereof which is brought into engagement with the periphery of the end of the lamp tube and the periphery of the fiare of the lamp mount when the lever 380 is rotated. Rotation of the lever 300 about the axis of the rod 302 is effected by the engagement of carn follower 306 on lever 300 with cam track 308 -(Figs. 1, 3a and 3b) which is mounted on the frame 20. A stop 310, mounted on the bedplate 156, defines and limits the end of this rotational movement of the lever 300 as it carries the puddling wheel 304 into its operating position. When the cam follower 306 leaves the cam track 308, the spring-loaded lever 300 is retracted by its spring.

As was mentioned above, each bank of heating units 26 comprises a plurality of burners 84, each of which is pivotally mounted at 86 on a burner-supporting rod 88 which is in turn supported from the frame 26 (Figs. 1 and 2). Referring now to Figures 11 and 12, each burner 84 comprises a metal tube 312, on one end of which a burner head 314 is mounted, the other end thereof being connected to the flexible tube 94) (Figs. 1, 2, 3a and 3b). The head 314 has a chamber 316 therein in register with and connected to the tube 312 and an arcuate slit 318 which defines the burner port.

The operation of the apparatus of our invention will now be described, starting with the driving of the conveyor chains 22 and the feeding of a lamp tube 11 and a pair of lamp mounts 13 to one of the heads 24. Referring first to Figures 1 and 2, the conveyor chains 22 are driven by the motor 38 through gear reduction mechanism 40, chain 42, sprocket wheel 44, shaft 46, gear reduction mechanism 48, conveyor drive shaft 36 and sprocket wheels 32. Each of the mount feeding mechanisms 28 is driven by the conveyor idler shaft 34 through gear 49 mounted thereon, gear 52 which meshes therewith and which is mounted on shaft 56, chain 56 which connects shaft 50 to shaft 60 through sprocket wheel 54 on shaft 50 and sprocket wheel 58 on shaft 60, and the mount feeding drive wheel 68 which is mounted on shaft 60 and around which the belt 64 which carries the clips 66 is caused to move. The endless metal belt 64, with the plurality of mount-carrying clips 66 mounted thereon, serves as a feeder for supplying mounts to the ends of each lamp tube, mounts being fed to the clips 66 by some suitable means. Although the lamp tubes may be fed to the lamp sealing apparatus by a suitable feeding mechanism, as was mentioned above, such a mechanism is not shown or decribed herein since it does not constitute an essential part of this invention. Therefore, insofar as this invention is concerned, the lamp tubes are fed to the heads 24 by an operator.

A lamp tube 11 is placed in the cradle 162 of the head 24 as the head completes its travel around the sprocket wheels 30 on the idler shaft 34 at the loading end of the lamp sealing apparatus. At this time the cradle 162 is disposed in the open position for the reception of a lamp tube therein, i. e., the openings in the pair of horse-shoeshaped bearings 164 are in register with the openings in the pair of plates 168 within which the bearings rotate, the segmental gear 188 is open with respect to the Segmental gear 190, pawl 234 is in locking engagement with ratchet wheel 232 thereby preventing the cradle 162 from being rotated (Fig. and the tube locking device 170 is in the open position to permit a lamp tube to be placed in the cradle 162 (Fig. 7). At this same time, each of the mount supporting mechanisms 166 is in its rest position, i. e., the bolt 248 is in the retracted position within the sleeve 250 and the yoke 284 on the bell-crank lever 278 is in the advanced position under the influence of the spring 292 which loads it.

As the head 24 moves from the loading end of the lamp sealing machine with a lamp tube 11 seated on the buttons 165 on the inside face of the bearings 164 of the cradle 162, the first operation performed thereon is retraction, at each end of the head, of the sleeve 251) within which the bolt 248 of the mount supporting mechanism 166 rides (Figs. 1, 3a and 3b). When the cam follower 282 on one end of bell-crank lever 278 rides up and along cam track 296 it causes the lever 27 8 to rotate about its pivot 280 and move the yoke 284 on the other end of lever 27% outwardly. Since the bearings 286 on yoke 284 ride in the groove 288 in the collar 2% mounted on sleeve 259, this outward movement of the yoke 284 effects outward movement of the sleeve 250 and places a load on the spring 292.

The next step is to effect axial alignment of a lamp mount 13 on each of the mount feeding belts 64 with the tube 11 in the cradle 162 and to move the mounts part way into the ends thereof so that they assume the position shown in the lowermost illustration in Figure 9. Since the belts 64 are driven from the shaft 34 on which sprocket wheels 30 of the head conveyor are mounted (Fig. 2), the mount-carrying clips 66 are spaced from one another on the belts 64 at a distance calculated to have a pair of mounts 13 brought into register with the longitudinal axis of the tube in the cradle 162 of the head 24. Movement of the mounts part way into the ends of the tube is effected by the angular disposition of the belts 64 (Fig. 1), as the mount-carrying clips 66 thereon approach their delivery position. Thus the mounts 13 are carried inwardly toward the ends of the tube 11 at the same time that the heads 24 and the belts 64 move forward in synchronism to bring the pair of mounts 13 and the tube 11 into axial alignment with one another.

With the tube and the pair of mounts disposed as just described, the next operation performed on the head 24 is movement of the mount spindle 252 of each of the mount supporting mechanisms into encompassing relationship with respect to the exhaust tube 15 and lead wires 17 of the lamp mount at each end of the tube (Figs. 1, 3a, 3b, and 9). This movement is effected when the cam follower 262 on pin 260 upstanding on bolt 248 engages and rides along cam track 264, which is inclined inwardly as shown in Figure 1. As the bolt 243 advances within its sleeve 250, the mount spindle 252 moves into encompassing relationship with respect to the exhaust tube and lead wires of the lamp mount, as shown in Figure 9, reading from the bottom to the top thereof.

While the mount spindles 252 of the mount feeding mechanisms 166 are moving into encompassing relationship with respect to the exhaust tubes and lead wires of the lamp mounts (Fig. 9), the tube locking device 170 (Figs. 1, 7 and 8) is actuated to lock the lamp tube in the cradle 162. This is effected when the camming face 186 on one end of the tube locking finger 176 strikes and moves past cam follower 181 supported on and depending from the frame 20 (Figs. 1 and 7). Thus the cam follower 181 effects rotation of the tube-locking finger 176 from the position shown in solid to the position shown in phantom in Figure 7 and brings the spring-loaded button 182 (Fig. 8) into frictional engagement with the lamp tube to hold it securely in position on the buttons on the bearings 164 of the cradle 162. Rotational movement of the tube-locking finger 176 to its closed position effects rotation of the shaft 174 on which it is mounted and this rotational movement of the shaft 174, in turn, effects rotation of the shaft 186 through the miter gears 178 and 184. Since the segmental gear 133 is mounted on the shaft 186, rotation of the shaft 186 swings the segmental gear 188 from the open position as shown in Figures 5 and 7 to the closed position, With the free end thereof in engagement with the projection 192 on the segmental gear 191) which is mounted on bearing 164. The lamp tube 11 is now locked in the cradle 162. by the tube-locking device and the gears 188 and 190 are closed with respect to one another and completely encircle the lamp tube.

When the lamp tube 11, the lamp mount 13 and the mount spindle 252 are in the relative position shown in the top illustration in Figures 9 and 10, the belt 64, to which the mount-carrying clip 66 is attached, starts its travel around the belt drive wheel 68. With the mount so constrained, the clip 66 frees itself of the mount as the belt 64 moves upwardly around the wheel 68.

The lamp tube is now securely held in its cradle 162 and the lamp mounts, in their spindles 252, are in position for sealing in at the ends of the tube. As the head 24 continues to move forward, the cam follower 242 on lever 240 rides up and along cam track 244 (Figs. 1, 3b and 5). As the cam follower 242 rides up the end of 9 the cam track 244 it deflects the lever 240 on which it is mounted and thereby effects rotation of the shaft 236 on one end of which the lever 240 is mounted. Since the pawl 234 is mounted on the other end of shaft 236, this rotation of shaft 236 moves the pawl 234 out of locking engagement with the ratchet wheel 232 (Fig. With the cam follower 242 riding along cam track 244 and the pawl 234 disengaged from the ratchet wheel 232, the head 24 continues to move forward and the sprocket wheel 208 engages the middle chain 210 of the triple chain conveyor 212 (Figs. 1, 3a and 3b). The triple chain conveyor 212 is driven bythe motor 222 (Figs. 1 and 2) throughshaft 226, sprocket wheel 224, chain 228, sprocket wheel 230, shaft 220 andsprocketwheels 218. The movevmentof the triple chain conveyor-212 is translated into rotation of the shaft 206 through the sprocket wheel 208 (Figs. '3 and 5). Rotation of the shaft 206 effects rotation of the lamp tube cradle 162 through gear 204 which meshes with gears 188 and 190 on thecradle. It also effects rotation of the sleeves 250 at each end of the head 24 through gears 254 which meshwith gears 256 mounted on the sleeves 250. At this point, the lamp tube and the lamp mounts are .being rotated at the same speed, in the same direction and on the same center line.

The next step to be performed is to securely seat the lamp mounts against the ends of the lamp tube since, up until this time, they are merely touching the ends. This is accomplished by .a short inward stroke of the sleeves 250, at each end of the head 24, which is made possible when the cam follower 282 at each end of the head 24 rides off of its track 296 and permits the spring loaded pin 294m draw the yoke 284 on the bell-crank lever 278 inwardly (Figs. 3a and 3b). Since the bearings 286 of yoke 284 ride in the groove 288 in the collar 290 mounted on the sleeve 250, the inward movement of the yoke 284 effects a similar inward movement of the sleeve 250. Since this inward movement of the sleeve 250 to bring the mount at each end of the tube into positive engagement therewith is accomplished by means of -a spring 292, damage to the mount and/or the end of the tube is avoided, the spring compensating for such variations in the length of this short stroke as may be necessary to insure a positive seating of the mount without the application of a force great enough to break the glass.

With the lamp mounts 13 securely seated against the ends of the lamp tube 11 and the lamp tube and the lamp mounts rotating, the tube and the mounts are ready for the application of heat thereto to seal them to one another. As was mentioned above, each bank of heating units 26 comprises a plurality of burners 84 mounted on a burner-supporting rod 88 which is reciprocated along its longitudinal axis and oscillated about its longitudinal axis at each end of the reciprocating stroke thereof (Figs. 1, 2, 3a and 3b). Since the head 24 which carries the members to be sealed is moving continuously, the reciprocating and oscillating strokes of the burner-supporting rods 88 are synchronized therewith. During the heating stroke of the reciprocation of each of the rods 88, the burners 84 are in heating relationship with respect to the ends mhe lamp tube as shown in Figures 3a and 3b. At the end of the heating stroke each of the rods 88 is oscillated to withdraw the burners 84 from their heating position, after which the return stroke of the reciprocation of the rod is effected, and then the rod is oscillated to return the burners to their heating position on a subsequent lamp tube and lamp mount assembly on a subsequent head 24.

The drive for reciprocating the burner-supporting rods 88 is taken off of shaft 46 (left side of Figure 2) which also drives the chains 22 on which the heads 24 are mountedv Rotational movement of the shaft 46 is transmitted into reciprocating movement of the burner-supporting rods 88 through gear 98, gear 100, shaft 102 (of which there are two, one on each side of the frame 20), miter gears 104 and 108 (of which there are two sets, one on each side of the frame 20 at one end of the shafts 102),

10 shaft 106 (on opposite ends of which a miter gear 108 is mounted), and ,a motion translating mechanism connected to each endof the shaft 106 comprising cam 110, cam follower 112 mounted on rocker arm 114, connecting rod 118, lever 120, shaft 122, lever 126, connecting rod 130 and extension 128 of burner supporting rod 88 (Figs. 1 and 2). The contour of the cam is such that it causes the rocker arm 114 to rotate counterclockwise about its pivot 116 (Figure 2), thereby moving the connecting rod 118 upwardly, the lever 120 clockwise, the lever 126 clockwise and the rod 88 to the left (Fig. 2) to eflfect the heating stroke of the burner-supporting rod 88. The return stroke of the burner-supporting rod 88 is also effected by the cam 110 which effects a reversal of operation of the several parts which are actuated by it.

The drive for oscillating the burners 84 into and out of heating position at the beginning and end respectively of the reciprocating stroke of the burner-supporting rods 88 is taken from the shafts 102 which are parallel to one another on opposite sides of the frame 20. Each shaft 102 has a pair of cams 142 mounted thereon, the cams being spaced from one another a distance substantially equal to the length of the burner-supporting rod 88. Rotary motion of the two shafts 102 is translated into oscillating motion of the two burner-supporting rods by four separate mechanisms, each of which comprises cam follower 144 which rides on the cam 142, rocker arm 146 pivoting about 148, connecting rod 150 and rod 152 upstanding on burner-supporting rod 88. The contour of the cam 142 is such that it effects oscillation of the burner-supporting rods 88 to bring the burners 84 into heating relationship with the ends of the lamp tube at the beginning of the reciprocating stroke of the rods 88 and .out of heating relationship at the end of this reciprocating stroke.

After the ends of the lamp tube with the mounts held securely thereagainst have been heated sufficiently, during several heating strokes .of the burner-supporting rods 88, to become tacky, the heads of the spindles 252, which, up until this point, have securely held the mounts seated in the ends of the lamp tube, are retracted slightly from engagement with the flare of the mount. This is accomplished by cam tracks 298 on opposite sides of the frame 20 (Fig. 1) which, when they are engaged by cam followers 282 (Figs. 3a and 3b), effect counterclockwise rotation of the bell-crank levers 278 and retraction of the sleeves 250 which carry the bolts 248 on which the spindles 252 are mounted.

The next operation which is performed is working of the molten glass to aid in the formation of the seal. This is accomplished by a pair of puddling devices mounted on the bedplate 156 of the head 24 beneath the ends of the lamp tube in the cradle 162 (Figs. 3a and 3b). When the cam follower 306 of each of the puddling devices rides up and along its cam track 308, it eflects rotation of the spring-loaded lever 300, on one end of which it is mounted, and swings the puddling wheel 304, which is mounted on the other end of lever 300, into engagement with the molten glass about the periphery of the ends of the lamp tube. Since the puddling wheel 304 is freely rotatable, the rotating lamp tube spins the wheel 304 and thereby effects a rolling of the seal to smooth it out uniformly about the entire periphery of the ends of the lamp tube.

When the seal-working operation has been completed, each of the cam followers 306 rides off of its track 308 and the spring-loaded lever 300, on which a load had been placed by its spring (not shown) when the lever advanced the puddling wheel 304 into seal-working position, swings back and returns the puddling wheel 304 to its normal rest position. Although the seal-working operation has been completed, the ends of the lamp tube are still heated during several subsequent heating strokes of the burner-supporting rods 88, primarily to effect an annealing of the seal.

Shortly after the head 24 moves past the last burner (Fig. 1) the cam follower 242 (Fig. 3b) rides oif of the track 244, thereby permitting the spring-loaded shaft 236 to rotate and throw the pawl 234 into locking engagement with the single tooth in the ratchet wheel 232. Locking of the pawl 234 with the ratchet wheel 232 arrests rotation of the shaft 206 on which the ratchet wheel is mounted and thus arrests rotation of the tubecarrying cradle 162 and the mount-carrying spindles 252 since these members are driven by the common shaft 206 as described above. The ratchet wheel 232 is provided with a single tooth located at a pre-determined position on the periphery thereof in order to make sure that, when rotation of the cradle 162 is arrested, the openings in the horse-shoe shaped bearings 164 of the cradle will be in register with the openings in the plates 168 within which the bearings rotate (Fig. 5), and the sleeves 250, within which the spindle bolts 248 are disposed, come to rest in the position shown in Figs. 3a and 3b, i. e., in position to permit cam followers 262 to engage cam tracks 266 at the unloading end of the apparatus, to permit withdrawal of the sealed lamp therefrom.

Although rotation of the cradle 162 and the spindles 252 has been arrested, the sprocket wheel 2% continues to rotate for the remainder of its travel along the middle chain 210 of the triple chain conveyor 212, the rotational force exerted thereby being absorbed by the friction clutch 247, 249 on the shaft 206.

After the sprocket wheel 2% leaves the middle chain 210 of the triple chain conveyor 212, the cam followers 262, mounted on pins 260 upstanding on bolts 248 of the mount supporting mechanisms 166 of the head 24 (Fig. 1), engage and ride along cam tracks 266, the contour of which is such that the bolts 248 are retracted, thereby freeing the sealed lamp tube from further contact therewith.

The tube locking device 170 and the segmental gear 188 are now swung to their open positions to permit withdrawal of the scaled lamp from the cradle 162 (Fig. 1). This is accomplished when the projection 196 on the face of plate 194 mounted on the segmental gear 188 strikes and moves past cam follower 326) mounted on the frame 20 and lying in the path traversed by the projection 196. The cam follower 32 constitutes an obstruction in the path of the projection 196 and causes the segmental gear 188, pivoting about the shaft 186 on which it is mounted, to swing open to the position shown in Figure 5. This rotation of the shaft 186 is transmitted through miter gears 184- and 173 (Fig. 8) and shaft 174 to the tube-locking finger 176 causing it to rotate from the closed position as shown in phantom in Figure 7 to the open position as shown in solid in this same figure. Thus the sealed lamp is now free to be withdrawn from its cradle 162 as the head 24 moves around sprocket wheels 32 and starts its return travel along tracks 167 to the loading end of the apparatus (Fig. 2). The sealed lamp may be permitted to roll out of its cradle 162 into a suitable receptacle or conveyor as the head 24 moves around the sprocket wheels 32 or it may be withdrawn therefrom either manually or mechanically.

What we claim is:

1. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for driving said conveyor; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for moving said spindles toward one another to bring the lamp mounts supported therein into engagement with the ends of the lamp tube in said cradle; means for rotating said cradle and said spindles with the lamp mounts in engagement with the ends of the lamp tube; and separate heating means located in operative relation to each of the lamp mounts in each of said spindles to fuse the lamp mounts supported therein to the ends of the lamp tube.

2. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for driving said conveyor; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for reciprocating said spindles toward and away from one another to advance the lamp mounts which they carry into engagement with the ends of the lamp tube in said cradle for the sealing operation and to retract said spindles to free them of the lamp mounts after the sealing operation has been effected; means for rotating said cradle and said spindles when the lamp mounts in said spindles are in engagement with the ends of the lamp tube in said cradle; heating means disposed in proximity to the paths traversed by said spindles; and means for moving said heating means into heating relationship with the lamp mounts in said spindles to fuse the lamp mounts to the ends of the lamp tube.

3. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for moving said conveyor continuously through a predetermined path; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for moving said spindles toward one another to bring the lamps mounts supported therein into engagement with the ends of the lamp tube in said cradle; means for rotating said cradle and said spindles with the lamp mounts in engagement with the ends of the lamp tube; heating means located in operative relation to said spindles to fuse the lamp mounts supported therein to the ends of the lamp tube; and a seal working means mounted on said head adjacent to each of said spindles and movable into engagement with the heated ends of the lamp tube and the lamp mounts.

4. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for driving said conveyor; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for moving said spindles toward one another to bring the lamp mounts supported therein into engagement with the ends of the lamp tube in said cradle; means for rotating said cradle and said spindles with the lamp mounts in engagement with the ends of the lamp tube; a plurality of burners located adjacent to the path traversed by each of said pair of spindles; and means for oscillating said plurality of burners into and out of heating relationship with the ends of the lamp tube and the lamp mounts to effect fusion thereof to one another.

5. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for moving said conveyor continuously through a predetermined path; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for moving said spindles toward one another to bring the lamp mounts supported therein into engagement with the ends of the lamp tube in said cradle; means for rotating said cradle and said spindles with the lamp mounts in engagement with the ends of the lamp tube; a plurality of burners located adjacent to the path traversed by each of said pair of spindles; and means for oscillating said plurality of burners into and out of heating relationship with the ends of the lamp tube and the lamp mounts, and for reciprocating said plurality of burners along a portion of the path traversed by said 13 conveyor and in heating relationship with the ends of the lamptube and the lamp mounts to eflect fusion thereof to one another.

6. Apparatus for sealing a lamp mount to each end of a lamp tube comprising'ra conveyor; means for driving said conveyor; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for reciprocating said spindles toward and away from one another to advance the lamp mounts which they carry into engagement with the ends of the lamp tube in said cradle for the sealing operation and to retract said spindles to free them of the lamp mounts after the sealing operation has been effected; means for rotating said cradle and said spindles when the lamp mounts in said spindles are in engagement with the ends of the lamp tube in said cradle; heating means disposed in proximity to the paths traversed by said spindles; means for moving said heating means into heating relationship with the lamp mounts in said spindles to fuse the lamp mounts to the ends of the lamp tube; and a seal working means mounted on said head adjacent to each of said spindles and movable into engagement with the heated ends of the lamp tube and the lamp mounts.

7. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for driving said conveyor; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for moving said spindles toward one another to bring the lamp mounts supported therein into engagement with the ends of the lamp tube in said cradle; means for rotating said cradle and said spindles with the lamp mounts in engagement with the ends of the lamp tube; a plurality of burners located adjacent to the path traversed by each of said pair of spindles; means for oscillating said plurality of burners into and out of heating relationship with the ends of the lamp tube and the lamp mounts to effect fusion thereof to one another; and a seal working means mounted on said head adjacent to each of said spindles and movable into engagement with the heated ends of the lamp tube and the lamp mounts.

8. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for moving said conveyor continuously through a pre-determined path; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for moving said spindles toward one another to bring the lamp mounts supported therein into engagement with the ends of the lamp tube in said cradle; means for rotating said cradle and said spindles with the lamp mounts in engagement with the ends of the lamp tube; a plurality of burners located adjacent to the path traversed by each of said pair of spindles; means for oscillating said plurality of burners into and out of heating relationship with the ends of the lamp tube and the lamp mounts, and for reciprocating said plurality of burners along a portion of the path traversed by said conveyor and in heating relationship with the ends of the lamp tube and the lamp mounts to effect fusion thereof to one another; and a seal working means mounted on said head adjacent to each of said spindles and movable into engagement with the heated ends of the lamp tube and the lamp mounts.

9. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for driving said conveyor continuously through a pre-determined path; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for reciprocating said -spindles toward and away from one another to advance the lamp mounts which they carry into engagement with the ends of the lamp tube in said cradle for the sealing operation and to retractsaid spindles to free them of the lamp mounts after the sealing operation has been effected; means for rotating said cradle and said spindles when the lamp mounts in .said spindles vare inengagement withthe ends of the lamp tube in said cradle; a plurality of burners located adjacent to the path traversed by each of said pair of spindles; means for oscillating said plurality of burners into and out of heating relationship with the ends of the lamp tube and the lamp mounts, and for reciprocating said plurality of burners along a portion of the path traversed by said conveyor and in heating relationship with the ends of the lamp tube and the lamp mounts to effect fusion thereof to one another; and a seal working means mounted on said head adjacent to each of said spindles and movable into engagement with the heated ends of the lamp tube and the lamp mounts.

10. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for driving said conveyor; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means for reciprocating said spindles toward and away from one another to advance the lamp mounts which they carry into engagement with the ends of the lamp tube in said cradle for the sealing operation and to retract said spindles to free them of the lamp mounts after the sealing operation has been eliected; means for rotating said cradle and said spindles when the lamp mounts in said spindles are in engagement with the ends of the lamp tube in said cradle; and heating means lo cated in operative relation to said spindles to fuse the lamp mounts supported therein to the ends of the lamp tube.

11. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for moving said conveyor continuously through a pre-determined path; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a cradle for supporting the lamp tube, said cradle being disposed between said spindles and in alignment therewith; means, synchronized with the movement of said conveyor, for feeding lamp mounts to said spindles; means for reciprocating said spindles toward and away from one another to advance the lamp mounts which they carry into engagement with the ends of the lamp tube in said cradle for the sealing operation and to retract said spindles to free them of the lamp mounts after the sealing operation has been elfected; means for rotating said cradle and said spindles when the lamp mounts in said spindles are in engagement with the ends of the lamp tube in said cradle; and heating means located in operative relation to said spindles to fuse the lamp mounts supported therein to the ends of the lamp tube.

12. Apparatus for sealing a lamp mount to each end of a lamp tube comprising: a conveyor; means for moving said conveyor continuously through a pre-determined path; a head mounted on said conveyor, said head comprising a pair of spindles for supporting the lamp mounts and a holder for supporting the lamp tube, said holder being disposed between said spindles and in alignment therewith; an endless conveyor, synchronized with the movement of said first-mentioned conveyor, for feeding lamp mounts directly to said spindles; means for reciprocating said spindles toward and away from one another to advance the lamp mounts which they carry into engagement with the ends of the lamp tube in said holder for the sealing operation and to retract said spindles to free them of the lamp mounts after the sealing operation has been effected; means for rotating said holder and said spindles when the lamp mounts in said spindles are in engagement with the ends of the lamp tube in said holder; and heating means located in operative relation to said spindles to fuse the lamp mounts supported therein to the ends of the lamp tube.

References Cited in the file of this patent UNITED STATES PATENTS 2,434,664 Malloy Jan. 20, 1948 16 Schneider Nov.30, 1948 Cartun Nov. 30, 1951 FOREIGN PATENTS Germany I an. 22, 1932 Great Britain Aug. 9, 1950 Austria June 11, 1951 

